TV Tokyo - is a television network. It has nothing to do with "anime studio". It falls in line with the likes of CW, FOX, Cartoon Network etc.... It is a multimedia network. It just doesn't focus on anime

CLAMP - is a group of manga artist. Not anime studio. They work on the manga side. it is up to the japanese networks to pick these up.

Aniplex, KyoAni
I don't generally keep super close track based off of studio but I don't think I've disliked anything that those two have produced/animated that I have seen.
Most recently Angel Beats, So Ra No Wo To, and the currently airing Oreimo from Aniplex and pretty much everything from KyoAni
Edit: Have to add SHAFT after watching some of the series they worked on.